I have a circut that need checking
I have a circut that need checking
(OP)
Ok, its a muiltiplexer w/ counter and clock that takes a 15 pin moniter input and compresses it into 1 line to be transmited. Also, does anyone know where I could find a small, compact, and cheap AM transmiter or schmatic for one? Also, smae requirments for a reciver
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Sorry the picture is small, I had to take a screenshout
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Sorry the picture is small, I had to take a screenshout





RE: I have a circut that need checking
You did not ask abut or show how you were going to do your sync. How will you send the clock, lock it, and recover the symbol slicer and sync to the data so you will not get mixed up as to which time slot is which pin? That is a big practical matter. You might want to pick a standard protocol.
Best Regards,
John Solar
RE: I have a circut that need checking
RE: I have a circut that need checking
/\/\/\/\____/\/\/\/\/\/\/\/\____
(10110)
into this:
______******_______________
|******|____|***************|____
The *s are place holders because the server doesn't like my illistration.
RE: I have a circut that need checking
RE: I have a circut that need checking
What are your real requirements?
John Solar
RE: I have a circut that need checking
RE: I have a circut that need checking
RE: I have a circut that need checking
For your keyboard and mouse, you may be talking PS/2 or USB. Both are analog.
You probably ment *Both are digital*
RE: I have a circut that need checking
How do I make this:
http://
Into this:
http://
I know I need a diode first, but what do I do after that?
RE: I have a circut that need checking
RE: I have a circut that need checking
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RE: I have a circut that need checking
Do you at all know what you are trying to do? Or how to achieve at least a little part of what you think you are going to do? Your postings are pointing in wildly different directions and I think that you should start from square one; that is mastering fundamentals like Ohms Law, simple basic circuits, quite a lot of signal math etcetera before you decide what you need/want to do. This will take you at least three years - more likely five years.
Asking a lot of questions here will not help you and those that are kind enough to try to help you will only get frustrated when they realise that you cannot benefit from what they say.
Gunnar Englund
www.gke.org
RE: I have a circut that need checking
I did mean analog. USB drivers and Rx are done with analog, since there are rise time fall time, voltage range requirements and a PLL clock recovery involved. SInce PS2 also has current sense as part of it's desing (like USB), I would consider that analog.
Stargate is correct. This is a very ambitious project. You must be doing this for a hobby, a learnign experience, or for school. Is so, taking on one small part of this might be a good place to start. If you just want to learn some electronics and are not involved in a formal education, there is the HAM radio community around the world and in many contries, the equivalent of a Radio Shack store/books.
Best Regards,
John Solar
RE: I have a circut that need checking
2.The orginial circute is the transmitter from the computer.
3.Then, I started working on the reciver. Then post with the really bad drawings of the sign wave and the analog wave were about that. How do you take the sign wave and make it into an analog wave?
4.Now, I don't know where to find a analog 1 to 16 bit demuiltiplexer. That was another queston.
5.Some responses asked how I planed to keep the multiplexer and demultiplexer in synic. I will do this by transmitting the output from the clock over a seporate transmitter (from the one that send the data). The reciver will used this signal. Again, that goes back to #3.
6.Both transmitters and both reciveres are going to be the same. The mouse only takes up 5 or 6 lines, as does the keybroad.
7.Forgive my spelling.
8.What is the Voltage requirements for the keyboard and mouse? (the moniter pluges into the wall, so its not a problem).
There it is, all layed out and explained in one post (for once). If I forgot something important (which I probably did), please tell me.
RE: I have a circut that need checking
Of the 15 pins, only 5 of them do anything useful for your transmitter. So, you only have to transmit 5 signal. Those are your 3 colors, and horizontal and vertical sync. The color is impedance controlled and in the MHz bandwidth range. That will preclude you from transmitting RF without a license unless you are ISM. The TDMA switching you propose may not be the best or the simplest. You could consider matrixing the 3 colors into I/Q phase and amplitude. This may better control your phase shifting (time shifting) of the colors. But this is standard practice and nothing new. You do not have to treat all 5 signal equally in your TDMA scheme. You might want to send the sync's over digitally.
You mentioned sending the clock over a side channel. This will not solve your sync problem. At best you will have a phase locked clock, which is good, but not good enough. There are several good books on communication sync and slicers, many from Europe.
The analog mux you are asking about is quite simple and perhaps the easiest part of your system. Hittite (spelling) is one low switch vendor with the BW you want. However, this mux will drive your A/D cost very high. It is much simpler to A/D each line and digitally mux them. Eight bits each at 5 MHz is 40 Mbit per second for the color.
This might help on the 15 pins:
h
There are many good books on the USB protocol. You might try Jan Axelson first.
http://www.lvr.com/
USB is bidirectional and is PC centric. The PC will poll your keyboard and mouse. If you use PS/2 for both you will eliminate the large overhead cost of USB.
Still PS/2 is a bi-directional serial protocol.
http://www.computer-engineering.org/ps2protocol/
You not only have to send the signal, but send or know who is doing the talking at each moment. This will be tricky in your scheme.
Power needed:
< 300 mA keyboard, mouse even less. Can be powered through your USB connection.
Is this a hobby or a learning exercise? It is much cheaper to purchase these large system solutions. I would recommend learning how to do each technology on a small project. Then when you master each one, you can approach a large project. You could read the back issues of Circuit Cellar Inc. to get good ideas on each of these topics.
Best Regards,
John Solar
RE: I have a circut that need checking
About just the 5 pins. how do I know what 5 pin I need and why is there 15 when they only need 5?
RE: I have a circut that need checking
RE: I have a circut that need checking
RE: I have a circut that need checking
I mentioned previously that 8 bits was enough.
I gave you a web site reference previously that gives you which 5 pins are for the 3 color and 2 sync lines, which are grounds, and which are inputs to the PC and which are open.
I gave you a web site link previously that gives the PS/2 ground and signal information and a web site reference to a book that has the USB information.
WiFi does not have the BW, the latency nor the QOS (Quality of Service) for your application.
If you do not have enough money for 30 laptops and a few workstations you do not have the money for the custom HW for this project.
RE: I have a circut that need checking
RE: I have a circut that need checking
RE: I have a circut that need checking